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Tough paper that won't burn, is resistant to bacteria and can be written on time and time again has been developed by US researchers.

The paper could be used in a range of applications, say scientists from the University of Arkansas in Fayetteville.

It could be used to make products from reusable bacteria filters to flame-retardant wallpaper that automatically decomposes airborne toxins.

Alternatively, it could be used to make rewritable, erasable, heat-resistant billboards along highways.

Its core ingredient is the key to the paper's resilience. While most paper is made from cellulose fibres, the new material is made from nanowires of titanium dioxide, a chemical compound common in white pigment.

"The starting materials are simple, non-toxic and inexpensive," says Dr Z Ryan Tian, assistant professor of chemistry and biochemistry at the university.

"The assembly is a room-temperature casting process, as simple as drying paper pulp."

To make the nanowires, the researchers first mix powdered titanium dioxide with an alkaline solution and place it in a teflon-coated container.

Then they heat the mixture in an oven at 150-250°C for one to several days.

As the alkali evaporates, it leaves behind long, white fibres.

The nanowires are washed in distilled water and, when still the consistency of wet pulp, cast into 3D shapes such as tubes, bowls and cups.

After the paper dries, it can be bent, folded or trimmed with scissors.

The finished product can withstand temperatures of 700°C, which makes it flame-retardant. It also makes it possible to sanitise the paper with a torch flame or ultraviolet light.

The paper's properties also make it ideal for a reusable filter membrane in gas masks, the researchers say.

The pore size of the paper can be adjusted during the casting process so that the holes are big enough to let oxygen in but small enough to block toxins.